Cardiovascular surgery is a surgery on the heart and/or great vessels performed by cardiac surgeons. Frequently, it is done to treat complications of ischemic heart disease (for example, coronary artery bypass grafting), correct congenital heart disease, or treat valvular heart disease caused by various causes including endocarditis. It also includes heart transplantation.
History
The earliest operations on the pericardium (the sac that surrounds the heart) took place in the 19th century and were performed by, Francisco Romero Dominique Jean Larrey, Henry Dalton, and Daniel Hale Williams. The first surgery on the heart itself was performed by Norwegian surgeon Axel Cappelen on the 4th of September 1895 at Rikshospitalet in Kristiania, now Oslo. He ligated a bleeding coronary artery in a 24 year old man who had been stabbed in the left axillae and was in deep shock upon arrival. Access was through a left thoracotomy. The patient awoke and seemed fine for 24hrs, but became ill with increasing temperature and he ultimately died from what the post mortem proved to be mediastinitis on the 3rd postoperative day. The first successful surgery of the heart, performed without any complications, was by Dr. Ludwig Rehn of Frankfurt, Germany, who repaired a stab wound to the right ventricle on September 7, 1896.
Surgery in great vessels (aortic coarctation repair, Blalock-Taussig shunt creation, closure of patent ductus arteriosus), became common after the turn of the century and falls in the domain of cardiac surgery, but technically cannot be considered heart surgery.
Heart Malformations – Early Approaches
In 1925 operations on the valves of the heart were unknown. Henry Souttar operated successfully on a young woman with mitral stenosis. He made an opening in the appendage of the left atrium and inserted a finger into this chamber in order to palpate and explore the damaged mitral valve. The patient survived for several years but Souttar’s physician colleagues at that time decided the procedure was not justified and he could not continue.
Cardiac surgery changed significantly after World War II. In 1948 four surgeons carried out successful operations for mitral stenosis resulting from rheumatic fever. Horace Smithy (1914–1948) of Charlotte, revived an operation due to Dr Dwight Harken of the Peter Bent Brigham Hospital using a punch to remove a portion of the mitral valve. Charles Bailey (1910–1993) at the Hahnemann Hospital, Philadelphia, Dwight Harken in Boston and Russell Brock at Guy’s Hospital all adopted Souttar’s method. All these men started work independently of each other, within a few months. This time Souttar’s technique was widely adopted although there were modifications.
In 1947 Thomas Holmes Sellors (1902–1987) of the Middlesex Hospital operated on a Fallot’s Tetralogy patient with pulmonary stenosis and successfully divided the stenosed pulmonary valve. In 1948, Russell Brock, probably unaware of Sellor’s work, used a specially designed dilator in three cases of pulmonary stenosis. Later in 1948 he designed a punch to resect the infundibular muscle stenosis which is often associated with Fallot’s Tetralogy. Many thousands of these “blind” operations were performed until the introduction of heart bypass made direct surgery on valves possible.
Open heart surgery
This is a surgery in which the patient's heart is opened and surgery is performed on the internal structures of the heart.
It was soon discovered by Dr. Wilfred G. Bigelow of the University of Toronto that the repair of intracardiac pathologies was better done with a bloodless and motionless environment, which means that the heart should be stopped and drained of blood. The first successful intracardiac correction of a congenital heart defect using hypothermia was performed by Dr. C. Walton Lillehei and Dr. F. John Lewis at the University of Minnesota on September 2, 1952. The following year, Soviet surgeon Aleksandr Aleksandrovich Vishnevskiy conducted the first cardiac surgery under local anesthesia.
Surgeons realized the limitations of hypothermia – complex intracardiac repairs take more time and the patient needs blood flow to the body (and particularly the brain); the patient needs the function of the heart and lungs provided by an artificial method, hence the term cardiopulmonary bypass. Dr. John Heysham Gibbon at Jefferson Medical School in Philadelphia reported in 1953 the first successful use of extracorporeal circulation by means of an oxygenator, but he abandoned the method, disappointed by subsequent failures. In 1954 Dr. Lillehei realized a successful series of operations with the controlled cross-circulation technique in which the patient's mother or father was used as a 'heart-lung machine'. Dr. John W. Kirklin at the Mayo Clinic in Rochester, Minnesota started using a Gibbon type pump-oxygenator in a series of successful operations, and was soon followed by surgeons in various parts of the world.
Dr. Nazih Zuhdi worked for four years under Drs. Clarence Dennis, Karl Karlson, and Charles Fries, who built an early pump-oxygenator. Zuhdi and Fries worked on several designs and re-designs of Dennis' earlier model from 1952–1956 at the Brooklyn Center. Zuhdi then went to work with Dr. C. Walton Lillehei at the University of Minnesota. Lillehei had designed his own version of a cross-circulation machine, which came to become known as the DeWall-Lillehei heart-lung machine. Zuhdi worked on perfusion and blood flow trying to solve the problem of air bubbles while bypassing the heart so the heart could be stopped for the operation. Zuhdi moved to Oklahoma City, OK, in 1957, and began working at the Oklahoma University College. Zuhdi, the heart surgeon, teamed up with Dr. Allen Greer, a lung surgeon and Dr. John Carey, forming a three man open heart surgery team. With the advent of Dr. Zuhdi's heart-lung machine which was modified in size, being much smaller than the DeWall-Lillehei heart-lung machine, and with other modifications, reduced the need for blood down to a minimal amount, and the cost of the equipment down to $500.00 and also reduced the prep time from two hours to 20 minutes. Dr. Zuhdi performed the first Total Intentional Hemodilution open heart surgery on Terry Gene Nix, age 7, on February 25, 1960, at Mercy Hospital, Oklahoma City, OK. The operation was a success; however, Nix died three years later in 1963. In March, 1961, Zuhdi, Carey, and Greer, performed open heart surgery on a child, age 3½, using the Total Intentional Hemodilution machine, with success. That patient is still alive.
In 1985 Dr. Zuhdi performed Oklahoma's first successful heart transplant on Nancy Rogers at Baptist Hospital. The transplant was successful, but Rogers, a cancer sufferer, died from an infection 54 days after surgery.
Modern beating-heart surgery
Since the 1990s, surgeons have begun to perform "off-pump bypass surgery" – coronary artery bypass surgery without the aforementioned cardiopulmonary bypass. In these operations, the heart is beating during surgery, but is stabilized to provide an almost still work area. Some researchers believe this approach results in fewer post-operative complications (such as postperfusion syndrome) and better overall results (study results are controversial as of 2007, the surgeon's preference and hospital results still play a major role).
Minimally invasive surgery
A new form of heart surgery that has grown in popularity is robot-assisted heart surgery. This is where a machine is used to perform surgery while being controlled by the heart surgeon. The main advantage to this is the size of the incision made in the patient. Instead of an incision being at least big enough for the surgeon to put his hands inside, it does not have to be bigger than 3 small holes for the robot's much smaller hands to get through.
Pediatric Cardiovascular Surgery
Pediatric Cardiovascular Surgery is surgery of the heart of children. Russell M. Nelson performed the first successful pediatric cardiac operation at the Salt Lake General Hospital in March 1956, a total repair of tetralogy of Fallot in a four-year-old girl.
Risks
The development of cardiac surgery and cardiopulmonary bypass techniques has reduced the mortality rates of these surgeries to relatively low ranks. For instance, repairs of congenital heart defects are currently estimated to have 4–6% mortality rates.
A major concern with cardiac surgery is the incidence of neurological damage. Stroke occurs in 2–3% of all people undergoing cardiac surgery, and is higher in patients at risk for stroke. A more subtle constellation of neurocognitive deficits attributed to cardiopulmonary bypass is known as postperfusion syndrome (sometimes called 'pumphead'). The symptoms of postperfusion syndrome were initially felt to be permanent, but were shown to be transient with no permanent neurological impairment
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